Modular Cryogenic Interconnects for Multi-Qubit Devices

TL;DR

This paper presents a modular cryogenic interconnect platform designed for scalable control and readout of multiple solid-state qubits, featuring high bandwidth, filtering, and separation capabilities at milli-Kelvin temperatures.

Contribution

The authors introduce a modular interconnect system with RF interposers that simplifies scaling and reduces complexity for multi-qubit device testing at cryogenic temperatures.

Findings

High-bandwidth control and readout achieved (>5 GHz)

Effective signal transmission with low crosstalk at milli-Kelvin temperatures

Modular design reduces complexity for multi-qubit device integration

Abstract

We have developed a modular interconnect platform for the control and readout of multiple solid-state qubits at cryogenic temperatures. The setup provides 74 filtered dc-bias connections, 32 control and readout connections with a bandwidth above 5 GHz, and 4 microwave feed lines that allow operation to above 10 GHz. The incorporation of a radio-frequency (rf) interposer enables the platform to be separated into two printed circuit boards, decoupling the simple board that is bonded to the qubit chip from the multilayer board that incorporates expensive connectors and components. This modular approach lifts the burden of duplicating complex interconnect circuits for every prototype device. We report the performance of this platform at milli-Kelvin temperatures, including signal transmission and crosstalk measurements.